The 54-year-old bandleader has quietly wed Houston lawyer and longtime love interest Cynthia McMurrey, 45, the Houston Chronicle reported Wednesday.
Among the late Frank Sinatra's hits was Love and Marriage, something the groom is trying for the first time. McMurrey is a divorcee.
They exchanged vows Sunday in a small ceremony at her father's home in Wharton, a farm town 55 miles southwest of Houston and one now swamped by major flooding.
Sinatra conducted his father's band until the retirement of the elder Sinatra, who died of a heart attack on May 14 at the age of 82.
Recently, Sinatra Jr. told CBS's Late, Late Show that his father had a hard time entering the September of his years.
"For a thoroughbred to age is never a graceful process," said Sinatra. "It was tough on him."
Sinatra also said the family never really believed the legend would die.
"Every family has deaths, but everybody has had this attitude that Sinatra was going to live forever," he said. "And this, I suppose, has to do with the fact that some people, they say, are larger than life."
In other news of Sinatra Jr., he recently won a round against the three men who kidnapped him in 1963. The kidnappers, who were convicted and served time for the crime, had been planning to profit from a movie about the incident.
Sinatra's legal action is preventing Columbia Pictures from paying Barry Keenan, Joseph Amsler, and John Irwin for their story. "While the perpetrators were eventually convicted and served time in prison for their crime, the Sinatra family has lived with the memories of that event ever since," Sinatra said when he filed suit in July. "Now those same individuals seek to capitalize on their crime."
He was held in a hideout in the San Fernando Valley for four days; the price of his release was a ransom of $240,000.